Well cleaner



J. E. HALL WELL CLEANER original Filed Jan. e, 1957 Patented Nov. 5, 1940 'UNITED STATES 2,220,237 I WELL CLEANER Jesse E. Hall, Los Angeles, Calif.

Application January 6, 1937, Serial No. 119,246 Renewed May 22, 1940 16 Claims: This invention relates to a well tool and relates more particularly to a well bore cleanery and casing centralizer. A general object of this invention is to provide a practical, inexpensive well bore cleaner and casing centralizer that is particularly effective in operation.

Another object of this invention is to provide improvements in the type of tool described and claimed in my co-pending application, Serial No. 38,891, flied September 3, 1935, entitled Casing attachment.

In the rotary method of well drilling it is the general practice to pump rotary mud through the well to cool and lubricate the drilling tools, to carry away the cuttings, etc. The rotary mud collects on the wall of the well bore and during the drilling operation may assist in preventing caving of the bore and the entrance of unwanted fluid to the well. However, when a casing is to be cemented in the well the coating of slime or mud on the Wall of the well bore prevents the cement from directly engaging and bonding with the earth formation and is often the cause of faulty and unsuccessful cementing operations. It has been found that the layer of mud on the wall of a well bore washes away and shrinks following the cementing of a casing and allows water or other unwanted fluids to enter the well.

Another ,object of the invention is to provide a Well bore cleaner adapted to be applied to a casing that is to be cemented in a well and that is operable to completely remove the mud from the wall of the well bore at the zone where the casing is to be cemented, whereby the cement may directly engage and unite with the virgin earth formation.

Another object of this invention is to provide a Well bore cleaner of the character mentioned that freely slides through the well when the casing is being run into the well without scoring or grooving the wall of the bore but at the same time plows through the mud and trowels it out to seal crevices in the formation.

Another object of this invention is to provide a well bore cleaner of the character mentioned that operates to smooth the wall of the bore and smooth, out or remove any stricture producing mud accumulations on the wall of the bore when the casing is run into the bore, thereby assuring a free circulation around the casing.

Another object of this invention is to provide a Well bore cleaner of the character mentioned that operates to scrape the layer or coating of mud from the wall of the well bore only during the upward movement of the casing whereby the operator may clean any selected portion of the bore to leave the original mud lining more compacted by the trowel action of the lowered tool on the remainder of the bore,

(Cl. 16B-18) Another object of this invention is to provide a well bore cleaner of the character mentioned that imparts a whirling orbital motio-n to mediaor cement flowing past it to assist in cleaning the bore and to prevent channeling of the cement.

Ano-ther object of this invention is to provide a full-circle scraper or bore cleaner and casing centralizer that dependably holds the casing spaced from the wall of the well bore to assure a complete and even distribution of the cement around the casing.

Another Object of this invention is to provide a well bore cleaner and casing centralizer that embodies flexible members or springs for engaging the wall of the well bore that are shaped to perform the functions or operations set forth above.

A further object of this invention is to provide a well bore cleaner and casing centralizer of the character mentioned embodying novel and dependable means for securing the springs or flexible members to the collars at the ends of the device. y

The various objects and features of my invention will be fully understood from the following detailed description of Ia typical preferred form and application of the invention, throughout which description reference is made to the accompanying drawing, in which:

Fig. 1 is a side elevation of a portion of a well casing showing two bore cleaners and centralizers of the invention arranged thereon. Fig. 2 is an enlarged transverse detailed sectional View taken as indicated by line 2 2 on Fig. 1. Fig. 3 is a transverse detailed sectional view taken as indicated by line 3 3 on Fig. 1. Fig. 4 is a fragmentary longitudinal sectional view taken as ind icated by line 4--4 on Fig. 3 'and Fig. 5 is a fragmentary side elevation of one of the collars showing a recess or groove therein for receiving the end portion of a flexible member.

The tool provided by this invention includes, generally, two sleeves or collars I0 to be slidably applied to a casing C and a multiplicity of outwardly bowed and spirally, or rather helically, curved springs or flexible members l-I extending between yand connecting the collars I0.

The sleeves or collars I0 are adapted to be applied to the casing C and serve to mount or support the flexible members Il which are de- .signed to engage the wall of the well bore. In A accordance with the invention there are two like collars l0 arranged in longitudinally spaced relation on the casing C. The collars l0 maybe tubular members having cylindrical internal and external surfaces. The peripheries of the outer end portions of the collars I0 may be slightly tapered as illustrated. The collars I0 are arranged on the casing C'for limited longitudinal movement.

The means for shiftably connecting the collars I 8 to the casing C are such that the collars may be easily and quickly applied to the casing when the same is to be run into the well. The means shiftably connecting or associating the collars I0 with the casing C include slots I2 in the collars I0. In practice there may be two diametrically opposite slots I2 in an end portion of each collar I-Ii. Two slots I2 may extend upwardly from the lower end of the upper collar I0 and two similar slots I2 may extend downwardly from the upper end of the lower collar III. 'I'he slots I2v are preferably pitched helically and the several slots preferably have the same pitch and are preferably pitched in the same direction. The slots I2 may be simple elongate openings of uniform width extending completely through the walls of the collars III.

The means for shiftably connecting the collars I Il with the casing C further include projections or lugs I3 on the casing C cooperating with the slots I2. 'I'he lugsl I3 may be simple block-like parts proportioned to readily enter the slots I2. The lugs I3 may be welded to the casing C to be rigid therewith. In practice the lugs I3 may be secured to the casing C in the manner described and claimed in my co-pending application referred to above. The lugs I3 may be Proportloned so that they do not project beyond the circumferences of the collars III. It is important that the lugs I3 be spaced and related to allow the collars I0 to have limited vertical movement along the casing C. The ends of the lugs I3 are adapted to cooperate with the inner end walls of the slots I2 to limit the movement of the collars I0 on the casing C. It will be noted that the lugs I3 cooperate with the grooves I2 in the opposing ends of the collars I0 and, therefore, cause the cleaner and centrallzer to be drawn downwardly through the well bore when the casing is moved downwardly as well as upwardly when the casing is moved upwardly.

'I'he shape and character of the springs or exible members II and their manner of connection with the collars I0 are features of the invention. The invention provides a plurality of circumferentially spaced flexible members II extending between and connecting the two spaced collars I0. I'he members I I may be equally clrcumferentially spaced and may be identical. In some instances, however, it may be desired to make the members II at one side of the device heavier or stronger to orient the casing C in a selected position in the well. In this regard it is to be noted that the lugs I3 cooperating with the slots I2 prevent relative rotation between the casing C and the bore cleaner so that the flexible members I I remain in substantially the same angular positions relative to the casing C. 'Ihe springs or flexible members II are provided to engage the wall of the well bore to smooth and clean the same and to hold the casing C substantially centralized in the bore. The members II are elongate flexible strips or leaf springs extending in the general direction of the longitudinal axis of the casing C.

The opposite end portions of the flexible members II are rigidly secured to the collars III. In accordance with the invention inclined or pitched grooves I4 are provided in the opposing end portions of the two spaced collars III. The grooves I4 are alike and are equally spaced about the collars III. 'I'he recesses or grooves I I are shaped and proportioned to receive the end portions of the flexible members II with substantial clearance. In `the preferred cnstructlon the grooves Il do not extend completely through the walls of the collars I0 and are only of sufllcient depth to properly receive the relative end parts of the flexible members II. Thus the inner surfacesof the members II bear against and are supported by the bottom walls Il of the relative grooves Il. This arrangement assures a good strong bearing for the end portions of the flexible members II.

In accordance with the invention a lug I8 projects from each side-wall and from the inner end wall of each groove I4. The lugs I8 are provided to cooperate with the side edges and the ends of the ilexible members I .I to hold the same spaced from the walls of the grooves I4 and thus leave spaces I'I around the edges of the parts of the members II received in the grooves I4. Fig. 5 of the drawing illustrates the end portion of a member II in broken lines and illustrates the manner in which the lugs I8 space the edges of the member II from the walls of the groove I4 to leave the spaces. I'I. It will be observed that the lugs I8 also definitely locate or orient the end portions of the members I I in the grooves I4. The spaces I1 between the walls of the grooves I 4 and the edges and ends of the flexible members II are filled with welds I8 which welds I8 rigidly secure the flexible members II to the collars I0. The welds I8 may completely occupy the above described spaces II but are preferably flush with the circumferences of the collars I0. The lugs I6 locate and centralize the end parts of the members II in the grooves I4 so that the welds I8 are of substantially uniform size and extent to dependably secure the members I I to the collars I0.

The members II for engaging the wall of the well bore are curved or bowed outwardly between their ends to have yielding bearing engagement with the wall of the bore. The members II are bowed outwardly from the collars I0 or from ad"- jacent the collars I 0, as illustrated in the drawing. In accordance with the invention the flexible members I I are pitched helically as well as bowed. 'Ihe members I I are all pitched in the same direction and at the same angle. In practice the members II and the grooves I 4 and the lugs I3 have the same angle or pitch. Because of this relationship the collars II) may screw or move at an angle when the members I I flex due to their engagement with the wall of the well bore. The flexible members II are bowed suilciently to all have bearing engagement with the wall of the well bore and this engagement causes elongate flattening of the members between their ends. The flexible members II preferably have a substantial helical pitch so that they cooperate to form a circle to engage the wall of the well bore throughout its entire circumference when the members are flattened along the Wall, as just described.

It is an important feature of this invention that the spring members I I have an inward twist or lateral twist or rake best illustrated in Fig. 2 of the drawing. It will be observed that the flexible members II are shaped or laterally twisted to be outwardly tangential relative to a circle concentric to the surface of the casing C, which circle is considerably smaller in diameter than the well bore represented by the broken circle in Fig. 2. This tangential twist or formation of the members II provides each member with what is here called a leading edge 20 and a trailing edge 2|. 'I'he upper portions of leading edges 20 of the members II are adapted to have scraping contact with the wall of the well bore when the device is moved upwardly in the well, but due to the shape or back, tangential twist of the members II the leading edges 20 have little or no scraping action during the downward movement of the device. During the downward movement of the device in the well the broad outer surfaces of the members II have sliding troweling engagement with the mud on the face wall of the bore to smooth and pack the same. The leading edges 20 of the members I I are particularly effective in scraping the wall of the well bore when the device is turned in a counter-clockwise direction when looking down upon it as in Fig. 2, While the broad outer surfaces of the members I I are effective in smoothing the mud and wall of the bore when the device is turned in the other direction. It is to be noted that the flexible members II are flexed tangentially to throw or direct the mud and sand inwardly toward the center of the bore as it is scraped away by the leading edges 20. The tangential twist of the members II also makes them effective in imparting a helical, orbital swirling motion to -a fluid that passes through the device. Thus the members II are effective in causing water or circulating fluid to better clean the wall of the well bore and in causing a better distribution of the cement about the casing C.

When the casing C is to be run into the well bore preparatory to the cementing operation one or more of the devices of the invention are applied to its lower portion. In assembling a cleaner and centralizer on the casing C the collars I0 carrying the members II are arranged on the casing and the lugs I3 are then secured to the casing, by welding, to properly cooperate with the slots I2 and to allow for the desired relative longitudinal movement between the collars I0. When two or more of the devices are provided on the lower end part` of the casing C it is preferred to relate them so that their flexible members II are oifset or circumferentially staggered. As the casing C is run into the well bore the flexible members II frictionally engage the wall of the bore and this engagement tends to resist movement of the members and the collars I0. Due to this drag of the members II against the Wall of the bore, the lower collars I0 of the device are pulled downwardly with the casing C by the lower lugs I3 cooperating with the slots I2 in the lower collars. Thus the devices are pulled downwardly in the well from their lower ends, leaving their upper collars I 0 free for axial movement on the casing C. This is important as it allows the ilexible members I I to flex freely as they bear on the wall of the bore Without danger of permanent distortion or failure of the members.

As described above, the tangential twist of the flexible members II is such that the members have a smoothing or troweling engagement with the wall of the bore during the downward movement of the device in the well. Accordingly, the members II operate to smooth the mud on the wall of the bore and to smooth away any restrictions of mud that may be present on the well bore to provide a better circulation around the easing C.v When the cleaners reach the portion of the well that is to receive the cement the casing C may be manipulated to cause the flexible members II to scrape the mud away from the wall of the bore. In practice the casing C may be recprocated or may be reciprocated and rotated so that the leading edges 20 of the members II eifectively scrape away the layer of mud on the wall of the bore. During upward movement of the casing C and during turning movement of the casing C in the proper direction the leading edges 20 of the members II are particularly effective in scraping away the mud from the wall of the bore. 'I'he back twist of the members I I is such that material thus scraped from the wall of the bore is directed inwardly on the broad surfaces of the members to be carried away by the Water or circulating fluid.

The collars I Il being free for limited vertical movement on the casing C allow the members I I to freely flex and properly conform to the Wall of the bore during the scraping or cleaning operation. The lugs I3 cooperate with the slots I2 for the transmission of turning forces from the casing C to the collars I0 so that the devices may be turned with the casing if desired. The members II are operable to trowel mud into crevices and entirely remove mud and slime from the hard wall of the bore to leave the well bore clean for the reception of the cement. During the cleaning operation water or other iluid may be circulated through the well to carry away mud, slime, etc. The tangentially and helically pitched members II operate to impart a swirling motion to this cleaning iluid. 'I'he spaced ilexible members II engage in a circle against the wall of the bore to hold the casing substantially centralized in the bore and when the cement is delivered to the well it may form a continuous annular body around the casing of substantially uniform thickness. This is important as it assures a dependable cement job.

Having described only a typical preferred form and applications of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims:

As clearly shown in Fig. 2, the springs II have such a helical curvature that each lower half of each spring II extends for a considerable are around the casing and the sum of all the arcs is such as to form nearly a complete bowl area. Fig. 1 shows that the springs overlap in axial projection to give a full circle trowel elfeet when the non-rotating tool is lowered in mud. When so lowered the mud that passes in between the springs is much agitated and helically swirled and is prevented from settling with increased viscosity while the tool is lowered.

This application is a continuation, in part, of my application Ser. No. 38,891, filed Sept. 3, 1935.

Having described my invention, I claim:

1. A well tool of the character described for use on a casing and including, spaced parts applied to the casing, and flexible members extending between and connected to said parts, said members being twisted both helically and tangentially as to the casing to each present a helical, out-bowed leading edge for scraping the wall of a bore and a trailing edge that is normally clear of the wall of the bore.

2. A well cleaner for external use on a cylindrical body, including a pair of spaced, co-axlal collars concentric to the body and having both a helical and a longitudinal sliding movement about and along the body, flexible, resilient, outwardly bowed, annularly spaced members rigidly con-` nected to the collars and providing for relative turn and shift of the collars, said members being equally pitched from collar to collar to permit and effect their relative rotation and having outer faces transversely oblique to a circle about the collar axis so as to bear on a well bore face and scrape it on stroke in one direction, and stop and guide means fixed on the body to effect a, pull action on the connected collars in axial movement of the body up or down and providing for both shift and rotation of the traveling collars; each collar being slidable on a respective part of said means.

3. A well cleaner for use on a casing including, collars having free limited longitudinal movement on the casing in spaced relation, and iiexible spirally curved members connecting the collars bowed outwardly to bear on the wall of the bore and twisted to scrape the said wall.

4. A well cleaner for use on a casing including, collars having limited longitudinal movement on the casing in spaced relation, and flexible members rigidly connected to the collars spiralled about the longitudinal axis of the casing, bowed outwardly between their ends and twisted about their individual axes, each member having spaced, overlapping relation as to those laterally adjacent.

5. In a casing appliance of the character described, a collar to be applied to the casing, said collar having an external helical groove, and a flexible member for engaging the wall of the bore and having its end portion secured in said groove.

6. An appliance for a well casing including, spaced collars for arrangement on the casing, means` connecting the collars with the casing to prevent their rotation thereon and allowing limited axial movement between the casing and collars, and spaced outwardly bowed, flexible, helical and oblique members connecting the collars to have scraping engagement with the wall of the well bore.

'7. A well cleaner for use on a casing including, collars for arrangement on the casing in spaced relation, means connecting the collars with the casing for limited vertical movement thereon, and a plurality of circumferentially spaced ilexible members extending between and secured to the collars for acting on the wall of the well, said members being bowed outwardly, spirally curved about the longitudinal axis of the casing and twisted laterally to have: wall scraping edges, the collars having slots with substantially the same spiral curvature as the flexible members, said means comprising lugs on the casing cooperating with said slots.

8. The cleaner of claim 2, and in which the said collars have their adjacent ends provided with helical slots between said members, and said xed stop and guide means including keys sliding in said slots and acting to hold one collar against screw action whilst the other moves with a screw action.

9. A device for use on a well casing including collars for arrangement on the casing in spaced relation, means connecting the collars with the casing for independent limited movement thereon, the collars having slots, said means including lugs on the casing cooperating with the slots, and

bowed flexible members connecting the collars and adapted to contact the Wall of the well bore to hold the casing centralized in the well.

10. A device for use on a well casing including collars for arrangement on the casing in spaced relation, the collars having openings, parts asados? adapted to be secured to the casing to cooperate with the openings to connect the collars to the casing for limited independent movement thereon, and ilexible members connecting the collars and bowed outwardly to cooperate with the bore of the well.

11. A device for use on well casing including collars for arrangement on the casing in spaced relation, means ixed to the casing to connect the collars therewith for limited helical movement therealong, and ilexible, helical members connecting the collars and moved outwardly to cooperate with the wall of the well bore.

12. A device for use on well casing including spaced collars adapted -to be arranged on the casing, lugs on the casing adjacent to each of the collars and engageable thereby to limit movement of the collars on the casing, and helical, flexible members attached to and extending between the collars and bowed outwardly to have contact with the wall of the Well to centralize the casing and clean the well.

13. A device for use on well casing including collars for arrangement on the casing in spaced relation, means connecting the collars with the casing for independent limited movement thereon, the collars having slots, said means including parts adapted to be attached to the casing to cooperate with the slots, and circumferentially spaced flexible members attached to the collars and bowed outwardly to have contact with the wall of the well bore, the members being pitched to overlap in their engagement with the well upon vertical movement of the casing, the slots being pitched in the same direction as such members.

14. A device for use on a tubular object to be run into a well, said device including collars surrounding the object at points spaced longitudinally thereof and movable thereon, each collar having a slot entering it from one end, outwardly bowed, helically pitched, flexible members extending between and connecting the collars, and elongate lugs on the object received in the slots and engageable with the ends of the slots to limit movement of the collars.

15. A device for use on a tubular object to be run into a well, said device including collars surrounding the object at points spaced longitudinally thereof and movable thereon, each collar having a slot; entering it from one end, outwardly bowed, flexible members extending between and connecting the collars, and elongate lugs fixed to the object to be received in the slots to limit the movement of the collars on the object, the lugs being of suflicient length to remain in the slots throughout the range of movement of the collars.

16. A device for use on a tubular object to be run into a well, said device including collars surrounding the object at points spaced longitudinally thereof and movable thereon, each collar having a slot entering it from one end, outwardly bowed, helically pitched, iiexible members extending between and connecting the collars, and elongate lugs on the object received in the slots and engageable with the ends of the slots to limit movement of the collars, the slots and the lugs being pitched in substantially the same direction as the members.

JESSE E. HALL. 

